ASTM D4662-08(2011)e1
(Test Method)Standard Test Methods for Polyurethane Raw Materials: Determination of Acid and Alkalinity Numbers of Polyols
Standard Test Methods for Polyurethane Raw Materials: Determination of Acid and Alkalinity Numbers of Polyols
SIGNIFICANCE AND USE
These test methods are suitable for quality control, as specification tests, and for research. The acid and alkalinity numbers indicate the extent of a reaction with acids. The results are measures of batch-to-batch uniformity and may be used as correction factors in calculating hydroxyl number.
SCOPE
1.1 These test methods measure the acidic and basic constituents in polyols and other materials of high acidity or alkalinity that are soluble in mixtures of toluene and ethyl alcohol. These test methods do not apply to polyethers. (See Note 1.)
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Note 1—There is no known ISO equivalent to this standard.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D4662 − 08(Reapproved 2011)
Standard Test Methods for
Polyurethane Raw Materials: Determination of Acid and
Alkalinity Numbers of Polyols
This standard is issued under the fixed designation D4662; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
´ NOTE—Editorially added Report and Precision and Bias information following Test Method A in February 2011.
1. Scope room temperature with alcoholic potassium hydroxide
solution, to the end point indicated by the color change of the
1.1 These test methods measure the acidic and basic con-
added phenolphthalein. Alkalinity numbers are determined by
stituents in polyols and other materials of high acidity or
back-titration after adding excess hydrochloric acid. The end-
alkalinity that are soluble in mixtures of toluene and ethyl
point of these titrations also can be determined potentiometri-
alcohol. These test methods do not apply to polyethers. (See
cally.
Note 1.)
5. Significance and Use
1.2 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
5.1 These test methods are suitable for quality control, as
responsibility of the user of this standard to establish appro-
specification tests, and for research. The acid and alkalinity
priate safety and health practices and determine the applica-
numbersindicatetheextentofareactionwithacids.Theresults
bility of regulatory limitations prior to use.
are measures of batch-to-batch uniformity and may be used as
correction factors in calculating hydroxyl number.
NOTE 1—There is no known ISO equivalent to this standard.
2. Referenced Documents 6. Reagents and Materials
2.1 ASTM Standards: 6.1 Purity of Reagents—Use reagent-grade chemicals in all
D883 Terminology Relating to Plastics tests. Unless otherwise indicated, it is intended that all reagents
D1193 Specification for Reagent Water conform to the specifications of the Committee on Analytical
Reagents of the American Chemical Society where such
3. Terminology
specifications are available. Other grades may be used pro-
3.1 Definitions—For definitions of terms used in these test
vided it is first ascertained that the reagent is of sufficiently
methods see Terminology D883.
high purity to permit its use without lessening the accuracy of
the determination.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 acid number—the quantity of base, expressed in mil-
6.2 Purity of Water—Unless otherwise indicated, references
ligramsofpotassiumhydroxide,thatisrequiredtotitrateacidic
to water shall be understood to mean reagent water as defined
constituents present in1gof sample.
by Type I of Specification D1193.
3.2.2 alkalinity number—the quantity of base, expressed as
6.3 Ethyl Alcohol, 95 %.
milligrams of potassium hydroxide, present in1gof sample.
6.4 Hydrochloric Acid (0.1 N)—Prepare a 0.1 N solution of
4. Summary of Test Method hydrochloric acid (HCl). Standardization is unnecessary.
4.1 The sample is dissolved in a mixture of toluene and
6.5 Phenolphthalein Indicator Solution—Dissolve 0.5 g of
ethyl alcohol. The resulting single-phase solution is titrated at
phenolphthalein in 100 mL of a mixture of equal volumes of
water and ethyl alcohol. Add a slight excess of 0.1 N NaOH
These test methods are under the jurisdiction of ASTM Committee D20 on
solution (pink color) and then just neutralize (colorless) with
Plastics and are the direct responsibility of Subcommittee D20.22 on Cellular
0.1 N HCl.
Materials - Plastics and Elastomers.
Current edition approved Feb. 1, 2011. Published March 2011. Originally
approved in 1987. Last previous edition approved in 2008 as D4662 - 08. DOI: Reagent Chemicals, American Chemical Society Specifications, American
10.1520/D4662-08R11E01. Chemical Society, Washington, DC. For suggestions on the testing of reagents not
For referenced ASTM standards, visit the ASTM website, www.astm.org, or listed by the American Chemical Society, see Analar Standards for Laboratory
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
Standards volume information, refer to the standard’s Document Summary page on and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
the ASTM website. MD.
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D4662 − 08 (2011)
6.6 Potassium Hydroxide, Standard Alcoholic Solution (0.1
B = KOH solution required for titration of the blank, mL,
N)—Dissolve 5.61 g of potassium hydroxide (KOH) in 10 mL
N = normality of the KOH solution, and
of carbon dioxide-free water and dilute to 1 L with ethyl
W = sample used, g.
alcohol. Store the solution in a chemical-resistant dispensing
10. Report
bottle protected by a guard tube containing soda-lime or
ascarite. Standardize frequently enough to detect changes of
10.1 For acid and alkalinity numbers below 7.0, report the
0.0005 N, preferably against pure potassium acid phthalate
value to the nearest 0.01.
(KHC H O , 0.8 to 0.9 g) in about 100 mL of carbon
8 4 4
10.2 For acid or alkalinity numbers of 7.0 or over, report the
dioxide-free water, using phenolphthalein to detect the end
value to the nearest 0.1.
point.
11. Precision and Bias
6.7 Sodium Hydroxide, Standard Solution (0.1 N)—Prepare
and standardize a 0.1 N solution of sodium hydroxide (NaOH).
11.1 Precision—Attempts to develop a precision and bias
statement for these test methods have not been successful. For
6.8 Titration Solvent—Mix equal volumes of toluene and
this reason, data on precision and bias
...
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